My questions for discussion are as following.

1) There are several methods to produce ultra-fine grained (UFG) metals (ferrous and non-ferrous) with grains less than 1 micron including SPD methods (ECAE(P), HPT, ARB, asymm. rolling-AR). However, I don't know examples of methods implemented in industrial steel production since 1970s when ECAE was invented. Why? I think due to discrete nature of processes. Does anybody know industrial applications of PSD?

2) There are a lot of publications on multiscale modeling of steel microstructure using standard FEM, special FEM, molecular dynamics methods (discrete elements, moving cellular automata) with quite nice images of simulations. How to varify results of simulations in grains boundary deformations and strains, grains growth and fragmentation as we will never have exactly the same pictures under microscope, moreover 2D instead of 3D. What criteria of microstructure models correctness? I think only statistical parameters of grains distribution (before and after deformation) can help in validation. Is any other opinions?